Dimethyl ether (DME) is a colorless and non-toxic gas commonly used as an aerosol propellant for both personal care and cooking products. More recently, DME has been introduced as a fuel for internal combustion engines.
DME fuel offers numerous advantages in comparison to more traditional fuels such as gasoline or diesel fuel. For example, vehicles such as tractor trailer combination vehicles with internal combustion engines that consume diesel fuel are known to produce particulate matter and soot as a byproduct of the combustion process. These vehicles are typically provided with relatively expensive exhaust after-treatment equipment such as diesel particulate filters to reduce such emissions. In contrast, the emissions from vehicles with internal combustion engines that use DME fuel are relatively clean and, in particular, include no particulate matter or soot. Thus the need for, and associated costs of, exhaust after-treatment equipment may be significantly reduced or even altogether eliminated for vehicles that consume DME fuel. Moreover, DME fuel has a higher cetane number than diesel fuel, and thus, the benefits of DME fuel may be realized without extensive changes to proven heavy duty compression ignition engine designs.
When DME is used as a fuel for internal combustion engines, an additive package is incorporated in the DME fuel to provide a lubricant for the fuel system components and an odorant to aid in leak detection. Where a vehicle design specifies inclusion of certain agents to a DME additive package, the absence or inadequacy of such agents may compromise DME fuel quality and vehicle operation. DME fuel quality may also be compromised by the introduction of contaminants such as water. The present invention provides improved solutions for determining the quality of DME fuel in a DME fuel storage and delivery system of a vehicle. In particular, exemplary embodiments provide solutions for determining when the protection and proper operation of a fuel storage and delivery system of a vehicle may be compromised by a lack of or a diminished level of lubricity agent in the DME fuel.